Flow stabilizing device for gun-type oil burners



March 24, 1953 L. @572 AL 2,632,500

FLOW STABILIZINC DEVICE FOR GUN-TYPE on. BURNERS Filed Oct. 4, 1950 2 SI-lEETS-Sl- EET 1 DELMOND L. GETZ & ROBERT o. HEDGES ATTORNEYS March 24, 1953 D. L. GETZ ETAL 3 FLOW STABILIZING DEVICE FOR GUN-TYPE OIL BURNERS Filed 001;. 4, 1950 ZSHEETS-SHEET 2 Pig-5 40 56 T WA 1 35 1g "4 A I A 12:22:23. a

gwvmvtow DELMOND L. GETZ 6; ROBERT 0. HEDGES ATTO R N EYS Patented Mar. 24, 1953 UNITED STATES PATENT OFFICE FLOW STABILIZING DEVICE FOR GUN- TYPE OIL BUBNERS Delmond L. Getz and Robert O. Hedges, Springfield, Ohio, assignors to The Steel Products Engineering Company, Springfield, Ohio, a corporation of Ohio Application October 4, 1950, Serial No. 188,449

7 Claims. 1 This invention relates to oil burners for heating purposes and the like.

One of the principal objects of the invention is to provide an oil burner in which the'liquid fuel is supplied-at a metered rate to an atomizing pump where it is mixed with air for delivery combustion.

It is a particular object of the invention to provide a flow stabilizingv device 'adaptedfor use in such an'oil burner which is effective to separate the atomized mixture of liquid fuel and air for separate delivery to the nozzle and which includes a pair of compartments separated by a differential diaphragm movable in accordance with the relative weight of the liquid fuel in the two compartments to control the rate of flow of the fuel to the nozzle.

It is also an object of the invention to provide a flow stabilizing device of the above characteristics in which the differential diaphragm embodies the control valve for regulating the flow of fuel to the nozzle to assure a steady and constant flow of fuel and to provide prompt adjustment compensating for variation in the rate at which the fuel is supplied to the flow stabilizing device.

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the apportion of the casing broken away;

Fig. 3 is an enlarged view of the flow stabilizing device of the oil burner of Figs. 1 and 2, the view being taken in section approximately on i the line 3-3 of Fig. 1 and also on the line of 3-4 of Fig.4;

Fig. 4 is a section onthe line 4-4 of Fig. 3; and Fig.5 is a section on the line 5-5 of Fig. 4. Referring to the drawings, which illustrate a preferred embodiment of the invention, Figs.

1 and 2 show the general construction of an oil burner incorporating an oil-metering pump in accordance with the invention, reference being made in this connection to our application Serial No. 2,713, filed January 16, 1948, of which 2 the present application is a continuation in part. The oil burner includes a main casing [3 having a base 14 and supporting an oil metering pump iii, an atomizing air pump l6 and a fan or blower 11, all driven by an electric motor 20 through a shaft 2|, and an adjustable damper 22 is provided for regulating the supply of air to the blower H. The oil from the supply tank .(not shown) is initially admitted to the metering pump by way of an inletconnection 24, and the pump [5 supplies this oil'at metered-rate to. the

atomizing pump it; where it is mixed withv air and then passed to the flow stabilizing device 25 by meansof a pipe ortube 26.- v

In the flow stabilizing device 25, the atomized mixture is. separated into air and liquidfuel for separate transmission to the nozzle 30in the combustion head 3| at the outer end of the blast tube 32. The air flows to the nozzle througha tube 33 to serve as primary air for mixture with the oil, which flows to the nozzle through a smaller tube 34 within the tube 33. At the nozzle, the liquid oil and primary air are mixed and ignited by a spark induced between the electrodes 35, which are provided with the proper high tension current by the transformer 36 on casing l3, and secondary air is supplied to the combustion head from the blower I1, the combustion head 3! having fins 31 thereon forcausing the secondary air to swirl as it is discharged from the blast tube.

The construction and operation of the flow stabilizing device 25 are shown in detail in Figs. 3 to 5. This device includes a bowl 40 bolted to the casing I 3 at 4| and provided with a cover 42 to enclose the chamber 44. The atomized mixture of oil and air from the pump 16 enters the chamber 44 from the pipe 23 by way of an inlet fitting 45 having a discharge tube 46 extend-i ing a substantial distance inwardly of the chamber 44 as shown. The bowl 40 includes an outlet at its opposite side from the inlet, whichis threaded to receive the end of the air tube 33, and the bowl 40 is also provided with a pair of ports 41 and 48 having removable screw plugs 49 therein as shown.

Within the chamber 44 is a casting 50 which is supported for sliding movement on two pins 5! set in the upper portion of the casting and supported by a bracket 52 secured to the under side of the top 42 of the bowl 411. Springs 53 are mounted on the pins 51 between the bracket 52 and the casting 50 in such position as to urge the casting towards the combustion head of the burner.. The casting 50 includes a central web portion 55, and passages 56 extend completely through the casting at either side of the web 55. At the center of the web there is formed. a tapered valve seat 6i) from which passages 6!, 62, 63 and 65 lead as shown in Fig. 4, and the oil tube 34 is threaded: into the outer end of the passage 64 and is thus supported within the air'tube' 33.

A circular corrugated diaphragm 65 of flexible material is secured to the upper surface'of the casting 50, and this diaphragm includes -a solid spherically curved portion 68 of bulbous shape which forms a valve adapted to seat on the valve seat fill. A cylindrical collar 10 is bolted to the casting 50 above the diaphragm 65, and it extends upwardlyto form therewith an inner compartment H within the chamber 44, leaving an outer compartment 72 surroundingzthe casting 50 within chamber 44 and communicating with the under side of the diaphragm 65 .through the passages 56. The length of the disichargei'tube 45*is such as'shownthatthe oil entering thebowl lo-through this tube will initially be idelivered into 'this compartment 1 l "Inthe'operationof this device, the-atomized "mixture of-oil'and' air'entering the bowl'Ml from "the'pump lfi'and' pipe 26 separates in the cham- "ber' 44,"the liquidoil-dropping initially into the inner-compartment H within-the collar "'lt'and *theair fllling'*the'remaining space. As shown in Fig. 3,-a"restricted1passage is provided at '75 Itbetween'the inner' end o'f'the tube 33 and the feasting 50, and the-air flows through this hassage to and through'the 'tube '33 'to'the nozzle for mixture with theoiland'combustion as described, the effective iiowarea of the passage "'15being-restricted to provide a throttling effect suflicient "to maintain a desired air pressure within chamber 44 for forcing the oil to the .nozzle.

lAt'the-start of the operation of 'the burner,

this'separatingaction continues as the oil "fills "the compartment =1 I thusforcing the diaphragm downwardly and urging its valve portion -66 into -closely sealed relation with the valveseat '6!) and preventing passage of oil to the nozzle. "When 'thiscompartmentis completely full, the "liquid oil overflows the top of the collar and begins to fill theouter-compartment n in the chamber. 'The oil spilling over from the inner compartment H rises in the outer compartment until it reaches a sufficient'height to exert pressure on 'the under surface "of the diaphragm 65 :by way of the passages tfiand thus to counteract the-"weight'of'the liquid in the compartment 'H "above the :diaphragm.

The proportions of "these severalparts are so *correlated that the e'fiective horizontal 'area of this inner compartment is less than thato'fthe --compartment lz and accordingly as soon .a 'the level of liquid in the outer part of the chamber has risen to "a sufficient level to balance the weight of'the oil above the diaphragm, it will cause the diaphragm to rise and thus 'to'unseat "its valve portion 66. 'Theliquid oil'will accordingly then be free to flow into the passage "6! r and thence by way of the passages 62, :63 and 64 to the'tube 34, and the pressure of the air in the upper part of the chamber will cause this desired fiow of'oil to the nozzle. The more the level of'oil rises within the chamber 44, the morethe-diaphragm will move to increase .the effective size of 'the clearance between the-'valve 66 and thevalve seat 60, allowing more liquid fuel to'pass through the nozzle until a balanced position-is reached at which the amountrof liquid fuel entering the chamber and the amount leaving by way of passage 6| will be equal.

After a balanced position of the valve and diaphragm is reached, the rate at which the liquid oil flows through the chamber will remain constant in'accordance with the output of the oil metering pump l5. .If there is a change in the output of the metering pump, the resulting -change in the level of liquid in the chamber will produce a-corresponding movement of the diaphragm until a balanced position is again reached. It should also be noted that with the "diaphragm of the configuration as shown, a substantial volumeof air will be entrapped under pressure in:the:annu1ar space H between the valve portion and the outer convolution of .:the:diaphragm,-and this air acts as a cushion toabsorb pulsations in the fuel supply from the pump Hi, this cushioning action being augmented by the air in the upper part of the chamber andalso by the free action of the diaphragm, thus assuring-a steady'and constant how of fuel to the 'nozzle.

"The burner will continue to operate at a constant rate so long as the oil output of the'metering pump I5 remains constant,'with the flow stabilizer providing-the desired steady and even iiow ofthe fuel'to the nozzle. Ifthe output to the metering pump should change, such change will be compensated for-by theaction of the diaphragm .G'Bas described to stabilize the operation of the burner at the new output level. When'theburner is shut off, by stopping motor 20, any liquid oil .remainingrinthe nozzle and 'thetube '34'wi1l1ten'd'to'drain backinto the bowl 40 in'preparation 'for'thernextsoperating cycle. When :themotor'is restarted, substantially the'same cycle .of operation will take place exceptthat since the chamber is already adequately filled with liquid oil, there will be no time delay for:filling'ithecompartments H and 12, and ignition will take .placealmost'immediately. Wheneveritl is tdesiredto drain the bowl,

this is "readily done .byremovin'g the "screw plugs 49 in'the ports '4'! and.

While the'form of apparatus hereindescribed "constitutes a preferred embodiment of the in- 'vention,.it is to be understood that the invention is not limited to'thisprecise'form of apparatus,

and that changes may be made therein without departing from the scope of the invention which is defined in the "appended claims.

What is claimed is:

'lMA flow stabilizingdevice "for use in an oil burner to receive a fuel mixture of airand oil for separation and separate delivery of the air and'liqui'd fuel to the burner nozzle, comprising a casing defining a closed chamber, a wall forming a pair of compartments in said chamber of difierent efiective volumes communicating with each other at the'top of said wall, a flexible diaphragm forming the bottom of *the smaller -of said compartments and having the under surfor oil from said chamber, means including a valve seat in said larger-compartment leading to said oil flow passage, a valve'movable with said diaphragm and adapted for seated engagement with said valve seat to close said oil passage, and an inlet for said fuel mixture to said chamber positioned to deliver the liquid oil thereininitially' to said smaller compartment for :filling said larger compartment by overflow from said smaller compartment-toacontrohthe position of said diaphragm and valve with respect to said valve seat in accordance with the rate of flow of liquid fuel into said chamber.

2. A flow stabilizing devicefor use n an oil burner to receive a fuel mixture of air and oil for separation and separate delivery'of the air and liquid fuel to the burner nozzle, comprising a casing defining a closed chamber, a wall defining a compartment in said chamber of lesser effective volume than the remaining open space in said chamber and communicating with said remaining space over the top of said wall, a flexible diaphragm forming the bottom of said compartment with both surfaces thereof open to pressure With:- in said chamber, a flow passage for air from the upper part of said chamber, a separate flow passage for oil from said chamber opening into said chamber below said diaphragm, a valve movable with said diaphragm and adapted to close said oil passage in one position of said diaphragm, and an inlet for said fuel mixture to said chamber positioned to deliver the li uid oil therein initially to said compartment for filling the remainder of said chamber by overflow from said compartment to cause said diaphragm and valve to move with respect to said oil passage in accordance with the rate of flow of liquid fuel into said chamber.

3. A flow stabilizing device for use in an oil burner to receive a fuel mixture of air and oil for separation and separate delivery of the air and liquid fuel to the burner nozzle, comprising a casing defining a closed chamber, a wall formin a compartment withinsaid casing of smaller effective volume than the remainder of said chamber, a diaphragm secured to said wall to form the bottom of said compartment, a support for said wall and diaphragm positioned to maintain said diaphragm in spaced relation with the bottom of said casing for access thereto by fluid within the portion of said chamber outwardly of said wall, a flow passage for air from the upper part of said chamber, a separate flow passage for oil from said chamber opening into said chamber at a position below said diaphragm. a valve movable with said diaphra m and adapted to seat on and close the open end of said passa e within said chamber, and an inlet for said fuel mixture to said chamber positioned to deliver the liquid oil therein initially to said compartment for filling the remainder of said chamber by overflow from said compartment to cause said diaphragm and valve to move with respect to said oil passa e in accordance with the rate of flow of liquid fuel into said chamber.

4. A flow stabilizing device for use in an oil burner to receive a fuel mixture of air and oil for separation and separate delivery of the air and liquid fuel to the burner nozzle, comprising a casing defining a closed chamber, a wall formin a pair of compartments in said chamber of d fferent effective volumes communicating with each other at the top of said Wall, a flexible diaphragm forming the bottom of the smaller of said compartments and having the under surface thereof open to pressure from said larger compartment, separate flow passages for air and for oil from ,said chamber, means including a valve seat in said larger compartment leading to said oil flow passage, a valve movable with said diaphra m and adapted for seated engagement with said valve seat to close said oil passage, an inlet for said fuel mixture to said chamber positioned t deliver the liquid oil therein initially to said smaller compartment for filling said larger compartment by overflow from said smaller compartment establishing a differential pressure condition on said diaphragm effective to regulate the position of said diaphragm and said valve with respect to said valve seat balancing the rate of flow of liquid fuel into said chamber nd ou through said passage, and means forming a pocket open on the lower side thereof to said larger compartment and closed on the upper side thereof by said diaphragm for entrapping air between said fining a compartment in said chamber of lesser effective volume than the remaining open space in said chamber and communicating with said remaining space over the top of said wall, a flexible diaphragm forming the bottom of said compartment with both surfaces thereof open to pressure within said chamber, an annular valve seat in said chamber below said diaphragm, a flow passage for oil from aid chamber leadin from said valve seat, a separate flow passage for air from the upper part of said chamber, an inlet for said fuel mixture to said chamber positioned to deliver the liquid oil therein to said compartment to fill the remainder of said chamher by overflow of said wall establishing a differential pressure condition effective on said diaphragm, and a valve movable with said diaphragm and adapted to seat on said valve seat to close said oil passage when the effective pressure on the upper surface of said compartment exceeds that on the lower surface thereof, said valve extending downwardly from the adjacent portion of said diaphragm to define therewith a space for entrapping air in the open position of said valve to provide a cushion for minimizing the effect on the oil flow thrOugh said passage of variations in the supply pressure to said chamher.

6. A flow stabilizing device for use in an oil burner to receive a fuel mixture of air and oil for separation and separate delivery of the air and liquid fuel to the burner nozzle,'comprising a casing defining a closed chamber, a wall defining a compartment in said chamber of lesser effective volume than the remaining open space in said chamber and communicating with said remaining space over the top of said wall, a flexible diaphragm forming the bottom of said compartment with both surfaces thereof open to pressure within said chamber, a flow passage for air from the upper part of said chamber, a separate flow passage for oil from said chamber opening into said chamber below said diaphragm, said diaphragm having a plurality of concentric convolutions therein and having a bulbous portion thereof extending downwardly at the center thereof to form a valve movable with said diaphragm and adapted to seat on and close the adjacent end of said oil passage, an inlet for said fuel mixture to said chamber positioned to deliver the liquid oil therein initially to said compartment for overflow therefrom to the remainder of said chamber to establish a differential pressure condition on said diaphragm effective to regulate the position of said diaphragm and valve with respect to said oil passage in accordance with the rate of flow of liquid fuel into said chamber, said valve cooperating with the adjaicentportions 0i said'diaphra m toiorman annular space forzentrappingpair -above the open ndof=-sa d oilpassa e to providea cushion for smin mizing the effect on the oil flow through :said passage of variations in the fuel suppl presc-sure to saidchamber.

"I, A flow .,.stabi1izing device for use in an oil burner tovreceive a fuel mixtureof air-and oil for separationand; separate delivery of the air and liquid Iuelto the burner nozzle, comprising a casqing-defininga closed. chamber, a body Withinsaid chamber, a wall carried by said body and cooprerating therewith to form a compartment within said-chamber of smaller efiectiveivolume than the rremainings ace. insaid. chamber, a iflexible .d'i i i-nhragmcooperating withsaid wall andr-said bo Morinthesbottom of: said'compartment, an an- 111111811 valve seat said body below said dia- "rphragm, an oil flow passage in said body leading from :said valve seat to said nozzle, a separate air flow-passage adapted to lead from the upper part of said chamber. tosaid nozzle,- a valve movable '*with said diaphr gm andadapted to seat on said valveseat-fcr .closingsaid oil passage said body having a passage therethrough providing a pressure connection between the under side of said diaphragm andthe portion of. said chamber outside said compartment, and an inlet for said fuel mixture to said chamber positioned to deliver the liquid oiltherein to said compartment for filling the remainder of said chamber by overflow of said Wall to establish a differential pressure condition effective on said diaphragm to regulate the position of said diaphragm and said valve with respect .to said valve seat in accordance with the rate of fiOWVOf liquid Vfuel into said chamber.

DELMOND L. GETZ. .ROBER'I O. HEDGES.

REFERENCES CITED Thefollowing references are of record the file of this patent:

UNITED STATES PATENTS 

